A Simple Gravimetric Method to Determine Barometer Corrections

Presented here is a gravimetric method to calibrate barometers. The difference in forces exerted on the pan of a balance is observed for two well characterized artifacts of nearly equal masses but different volumes. During the weighing, air temperature and relative humidity are measured; the ambient pressure is then calculated from an air density equation. A barometer correction is derived and then compared to an independent value based on a standard barometer. The data indicate that pressure can be calculated with an uncertainty (1 S.D.) of not more than 400 ppm at one atmosphere.